<?php
/**
 * Created by PhpStorm.
 * User: cqfut
 * Date: 2018/10/31
 * Time: 15:37
 */

function deleteDir($dir)
{
    $handle = opendir($dir);
    if ( !$handle ) {
        return false;
    }
    $file = readdir($handle);
    while ( false !== $file ) {
        //排除当前目录与父级目录
        if ($file !== "." && $file !== "..") {
            $file = $dir . '/' . $file;
            if (is_dir($file)) {
                deleteDir($file);
            } else {
                unlink($file);
            }
        }
        $file = readdir($handle);
    }
    rmdir($dir);
}

function crypto_rand_secure($min, $max) {
    $range = $max - $min;
    if ($range < 0) {
        return $min; // not so random...
    }
    $log = log($range, 2);
    $bytes = (int) ($log / 8) + 1; // length in bytes
    $bits = (int) $log + 1; // length in bits
    $filter = (int) (1 << $bits) - 1; // set all lower bits to 1
    do {
        if(function_exists("openssl_random_pseudo_bytes")){
            $rnd = hexdec(bin2hex(openssl_random_pseudo_bytes($bytes)));
        }
        else{
            $rnd = hexdec(bin2hex(rand()."_".rand()));
        }
        $rnd = $rnd & $filter; // discard irrelevant bits
    } while ($rnd >= $range);
    return $min + $rnd;
}

function getToken($length=32){
    $token = "";
    $codeAlphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    $codeAlphabet.= "abcdefghijklmnopqrstuvwxyz";
    $codeAlphabet.= "0123456789";
    for($i=0;$i<$length;$i++){
        $token .= $codeAlphabet[crypto_rand_secure(0,strlen($codeAlphabet))];
    }
    return $token;
}

/**
 * 生成密码
 * @param $password  表示密码的字符串
 * @param bool $md5ed 密码是否经过md5加密处理
 * @return string 经过处理后的密码串
 */
function pwGen($password,$md5ed=false)
{
    if (!$md5ed) {
        $password = md5($password);
    }
    $salt = sha1(rand()); // sha1会返回40个字符的16进制数
    $salt = substr($salt, 0, 4);
    $hash = base64_encode( sha1($password . $salt, true) . $salt );
    return $hash;
}

/**
 * 验证用户输入的密码是否正确
 * @param $password 用户输入的密码
 * @param $md5ed 用户输入的密码是否已经过md5加密
 * @param $saved  数据库中保存的密码
 */
function pwCheck($password, $md5ed, $saved)
{
    $svd=base64_decode($saved);
    $salt=substr($svd,20);
    if ( !$md5ed ) {
        $password = md5($password);
    }
    $hash = base64_encode( sha1(($password) . $salt, true) . $salt );
    if (strcmp($hash,$saved)==0) return True;
    else return False;
}

/**
 * 判断给定的字符串是否是md5字符串
 * @param $str 给定字符串
 */
function isMd5Str($str)
{
    if(strlen($str)!=32) {
        return false;
    }
    $ret = true;
    for ($i=0; $i < strlen($str); $i++) {
        $c = $str[$i];
        if ('0'<=$c && $c<='9') {
            continue;
        }
        else if ('a'<=$c && $c<='f') {
            continue;
        }
        else if ('A'<=$c && $c<='F') {
            continue;
        }
        else {
            $ret = false;
            break;
        }
    }
    return $ret;
}

/**
 * 输入的用户名是否是有效的用户名
 * @param $user_name
 * @return bool
 */
function isValidUserName( $userName ) {
    $len=strlen($userName);
    $ret = true;
    for ($i=0;$i<$len;$i++) {
        $c = $userName[$i];
        if ('0'<=$c && $c<='9') {
            continue;
        }
        else if ('a'<=$c && $c<='z') {
            continue;
        }
        else if ('A'<=$c && $c<='Z') {
            continue;
        }
        else {
            $ret = false;
            break;
        }
    }
    return $ret;
}

function sec2str($sec){
    return sprintf("%02d:%02d:%02d",$sec/3600,$sec%3600/60,$sec%60);
}

function RemoveXSS($val) {
    // remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed
    // this prevents some character re-spacing such as <java\0script>
    // note that you have to handle splits with \n, \r, and \t later since they *are* allowed in some inputs
    $val = preg_replace('/([\x00-\x08,\x0b-\x0c,\x0e-\x19])/', '', $val);

    // straight replacements, the user should never need these since they're normal characters
    // this prevents like <IMG SRC=@avascript:alert('XSS')>
    $search = 'abcdefghijklmnopqrstuvwxyz';
    $search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
    $search .= '1234567890!@#$%^&*()';
    $search .= '~`";:?+/={}[]-_|\'\\';
    for ($i = 0; $i < strlen($search); $i++) {
        // ;? matches the ;, which is optional
        // 0{0,7} matches any padded zeros, which are optional and go up to 8 chars

        // @ @ search for the hex values
        $val = preg_replace('/(&#[xX]0{0,8}'.dechex(ord($search[$i])).';?)/i', $search[$i], $val); // with a ;
        // @ @ 0{0,7} matches '0' zero to seven times
        $val = preg_replace('/(&#0{0,8}'.ord($search[$i]).';?)/', $search[$i], $val); // with a ;
    }

    // now the only remaining whitespace attacks are \t, \n, and \r
    $ra1 = Array('javascript', 'vbscript', 'expression', 'applet', 'meta', 'xml', 'blink', 'link', 'style', 'script', 'embed', 'object', 'iframe', 'frame', 'frameset', 'ilayer', 'layer', 'bgsound', 'title', 'base');
    $ra2 = Array('onabort', 'onactivate', 'onafterprint', 'onafterupdate', 'onbeforeactivate', 'onbeforecopy', 'onbeforecut', 'onbeforedeactivate', 'onbeforeeditfocus', 'onbeforepaste', 'onbeforeprint', 'onbeforeunload', 'onbeforeupdate', 'onblur', 'onbounce', 'oncellchange', 'onchange', 'onclick', 'oncontextmenu', 'oncontrolselect', 'oncopy', 'oncut', 'ondataavailable', 'ondatasetchanged', 'ondatasetcomplete', 'ondblclick', 'ondeactivate', 'ondrag', 'ondragend', 'ondragenter', 'ondragleave', 'ondragover', 'ondragstart', 'ondrop', 'onerror', 'onerrorupdate', 'onfilterchange', 'onfinish', 'onfocus', 'onfocusin', 'onfocusout', 'onhelp', 'onkeydown', 'onkeypress', 'onkeyup', 'onlayoutcomplete', 'onload', 'onlosecapture', 'onmousedown', 'onmouseenter', 'onmouseleave', 'onmousemove', 'onmouseout', 'onmouseover', 'onmouseup', 'onmousewheel', 'onmove', 'onmoveend', 'onmovestart', 'onpaste', 'onpropertychange', 'onreadystatechange', 'onreset', 'onresize', 'onresizeend', 'onresizestart', 'onrowenter', 'onrowexit', 'onrowsdelete', 'onrowsinserted', 'onscroll', 'onselect', 'onselectionchange', 'onselectstart', 'onstart', 'onstop', 'onsubmit', 'onunload');
    $ra = array_merge($ra1, $ra2);

    $found = true; // keep replacing as long as the previous round replaced something
    while ($found == true) {
        $val_before = $val;
        for ($i = 0; $i < sizeof($ra); $i++) {
            $pattern = '/';
            for ($j = 0; $j < strlen($ra[$i]); $j++) {
                if ($j > 0) {
                    $pattern .= '(';
                    $pattern .= '(&#[xX]0{0,8}([9ab]);)';
                    $pattern .= '|';
                    $pattern .= '|(&#0{0,8}([9|10|13]);)';
                    $pattern .= ')*';
                }
                $pattern .= $ra[$i][$j];
            }
            $pattern .= '/i';
            $replacement = substr($ra[$i], 0, 2).'<x>'.substr($ra[$i], 2); // add in <> to nerf the tag
            $val = preg_replace($pattern, $replacement, $val); // filter out the hex tags
            if ($val_before == $val) {
                // no replacements were made, so exit the loop
                $found = false;
            }
        }
    }
    return $val;
}
